A Study to Learn More About the Long-Term Safety and Effects of Felzartamab Infusions in Adults With Kidney Transplants Who Have Antibody-Mediated Rejection (AMR)

The primary objective of this study is to evaluate the long-term safety of felzartamab. The secondary objectives of this study are to describe the ongoing efficacy of felzartamab on biopsy-proven histologic response (BPHR), microvascular inflammation (MVI) and graft function; to evaluate the ongoing efficacy of felzartamab by monitoring circulating donor-derived cell-free DNA (dd-cfDNA) and to evaluate pharmacokinetics (PK) and immunogenicity of felzartamab.